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SUPPLEMENTARY INFRMATIN Activating efficient phosphorescence from purely-organic materials by crystal design nas Bolton 1, Kangwon Lee 1, Hyong-Jun Kim 1, Kevin Y. Lin 2, Jinsang Kim 1,2,3,4 1 Department of Materials Science and Engineering, 2 Department of Chemical Engineering, 3 Departments of Macromolecular Science and Engineering, 4 Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 Supplementary Methods H H (i) C 6 H 13 C 6 H 13 (ii) CH C 6 H 13 C 6 H 13 6, 70-80% 6A, 50-70% 2 1 Cl Cl MgC 7 H 15 (dppp)nicl 2 Et 2, r.t., 24h (iii) C 7 H 15 C 7 H 15 C 7 H 15 C 7 H 15 C6, 53% 1. nbuli, THF, -78 o C, 1h (iii) C 6 H 13 S SC 6 H 13 C 6 H 13 S SC 6 H 13 2. S 2 (C 6 H 13 ) 2, r.t., 3h S6, 46% 4 6 (ii) (ii) CH C 7H 15 C 7H 15 C6A, 93% 3 CH C 7 H 15 C 7 H 15 S6A, 50% 5 H (i) C 6 H 13 2x 2, 0.4x Fe H C 6 H 13 CCl 4,0 o C, 20 min CH C 6 H 13 (ii) C 6 H 13 C 6 H 13 Np6, 77% 8 C 6 H 13 Np6A, 7% Supplementary Scheme 1. General synthesis of compounds presented. (i) 2.5 equiv. C 6 H 13, 3 equiv. K 2 C 3, DMF, 70-90 o C, 24-48h. (ii) 1. 1 equiv. nbuli, THF, -78 o C, 1h, 2. 4 equiv. DMF, 23 o C, 3h. (iii) 2.05 equiv. 2, cat. I 2, CH 2 Cl 2, 24h. 7 nature chemistry www.nature.com/naturechemistry 1

supplementary information Compounds are numbered as they appear in the main text. Here each is listed in their synthetic order as the aldehydes chromophores are produced from the dibromo hosts. 2,5-dihexyloxy-1,4-dibromobenzene (6, 2). The title compound was synthesized via the route reported by Kim and coworkers, modified as below. 24 2,5- dibromohydroquinone (1 equiv.) and 1- bromohexane (2.1 equiv.) are loaded into a glass flask and dissolved into dimethylformamide (ca. 1 ml solvent / g dibromohydroquinone). Potassium carbonate (3 equiv.) is added and the flask is stirred and refluxed for 24 hours. The reaction is then cooled and filtered. The product is purified by silica column chromatography with hexanes. White/colorless crystals were collected at yields of 70-80%. 1 H NMR (500 MHz, CDCl 3 ): δ 7.05 (s 2H), 3.91 (t 4H), 1.76 (m 4H), 1.43 (m 4H), 1.33 (m 8H), 0.91 (m 6H). 2,5-dihexyloxy-4-bromobenzaldehyde (6A, 1). The tile compound was synthesized H via the route reported by Wu and Lin, modified as below. 25 2,5-dihexyloxy- 1,4-dibromobenzene (6 2, 1 equiv.) is loaded into a glass flask and vacuum purged with argon three times. Anhydrous tetrahydrofuran, dried over sodium metal, is added (ca. 25 ml solvent / g 6) and the vessel is placed into a bath of dry ice and 2-propanol. n-butyllithium (1 equiv.) in hexanes is added dropwise and the reaction is stirred for 1 hour. Anhydrous 2 nature chemistry www.nature.com/naturechemistry

supplementary information dimethylformamide (4 equiv.) is then added and the reaction is allowed to warm to 23 o C over three hours. The reaction is quenched carefully with water and extracted with diethylether. Purification was done by silica column chromatography with ethylacetate:hexane (1:30) followed by recrystallizations from methanol and acetonitrile. White/colorless crystals were collected at yields of 50-70%. 1 H NMR (500 MHz, d 6 - DMS): δ 10.29 (s 1H), 7.53 (s 1H), 7.23 (s 1H), 4.09 (t 2H), 4.01 (t 2h), 1.73 (m 4H), 1.42 (m 4H), 1.30 (m 8H), 0.87 (m 6H). 1,4-dibromo-2,5-diheptylbenzene (C6, 4). The title compound was synthesized through a Grignard synthesis and subsequent bromination as presented by Rehahn and coworkers. 26 White/colorless crystals were collected at a 53% yield. 1 H NMR (500 MHz, CDCl3): δ 7.71 (s 2H), 2.65 (t 4H), 1.57 (m 4H), 1.37-1.31 (m 16H), 1.08 (m 6H). 4-bromo-2,5-diheptylbenzaldehyde (C6A, 3). The title compound was synthesized H from C6 4 via the formylation procedure of 6A. Final purifications were done by silica column chromatography with ethylacetate:hexane (1:30). A clear liquid that crystallized days later was collected at a yield of 93%. 1 H NMR (500 MHz, CDCl 3 ): δ 10.22 (s 1H), 7.64 (s 1H), 7.46 (s 1H), 2.94 (t 2H), 2.74 (t 2H), 1.59 (m 4H), 1.43-1.22 (m 16H), 0.88 (m 6H). 13 C NMR (400 MHz, CDCl 3 ): δ = 14.0, 22.6, 29.1, 29.3, 29.4, 29.7, 31.6, 31.7, nature chemistry www.nature.com/naturechemistry 3

supplementary information 31.7, 32.3, 35.6, 131.0, 132.3, 132.6, 135.0, 140.5, 144.5, 191.4. MS (EI): found = 380.1715 (M + ), calcd for C 21 H 33 (M + ) = 380.1714. H 4 nature chemistry www.nature.com/naturechemistry

supplementary information (2,5-dibromo-1,4-phenylene)bis(hexylsulfane) (S6, 6). The title compound was synthesized from a thiolation like that S S of Gao and coworkers followed by bromination. 27 1,4-Dibromobenzene is loaded into a glass flask and vacuum purged with argon three times. Anhydrous tetrahydrofuran, dried over sodium metal, is added (ca. 10 ml solvent / g) and the vessel is placed into a bath of dry ice and 2-propanol. n-butyllithium (2.1 equiv.) in hexanes solution is added dropwise and the reaction is stirred for 1 hour. Di-n-hexyldisulfide (2 equiv.) is then added and the reaction is allowed to warm to 23 o C over three hours. The reaction is quenched carefully with water and extracted with diethyl ether. Purification is done by silica column chromatography with hexanes. A pungent, slightly yellow oil is collected in yields of 20-30%. The product is brominated via the same reaction conditions of Rehahn and coworkers 26 and purified by column chromatography with hexanes followed by recrystallization from methanol. Fine white crystals were collected at a yield of 46%. 1 H NMR (500 MHz, CDCl 3 ): δ 7.37 (s 2H), 2.91 (t 4H), 1.70 (m 4H), 1.49 (m 4H), 1.33 (m 8H), 0.90 (m 6H). 13 C NMR (400 MHz, CDCl 3 ): δ = 14.0, 22.5, 28.2, 28.6, 31.3, 33.4, 122.5, 131.3, 136.7. MS (EI): found = 466.0007 (M + ), calcd for C 18 H 28 2 S 2 (M + ) = 465.9999. nature chemistry www.nature.com/naturechemistry 5

supplementary information S S 6 nature chemistry www.nature.com/naturechemistry

supplementary information 4-bromo-2,5-bis(hexylthio)benzaldehyde (S6A, 5). The title compound was H synthesized from S6 via the formylation procedure of 6A. S S Products were purified by column chromatography with ethylacetate: hexane (1:30) followed by recrystallization from methanol. Yellow crystals are collected at a yield of 50%. For S6A, 1 H NMR (500 MHz, CDCl 3 ): δ 10.39 (s 1H), 7.64 (s 1H), 7.61 (s 1H), 3.00 (t 2H), 2.91 (t 2H), 1.73-1.65 (m 4H), 1.46 (m, 4H), 1.34-1.28 (m 8H), 0.89 (m 6H). 13 C NMR (400 MHz, CDCl 3 ): δ = 14.0, 22.5, 28.2, 28.5, 28.5, 31.3, 31.3, 33.0, 34.4, 128.6, 129.7, 133.5, 133.6, 137.5, 139.0, 190.4. MS (EI): found = 416.0850 (M + ), calcd for C 19 H 29 S 2 (M + ) = 416.0843. nature chemistry www.nature.com/naturechemistry 7

supplementary information H S S 8 nature chemistry www.nature.com/naturechemistry

supplementary information 1,5-dibromo-2,6-bis(hexyloxy)naphthalene (Np6, 8). The title compound was synthesized from naphthalene-2,6- diol, which was converted to 2,6- bis(hexyloxy)-naphthalene by Williamson ether synthesis similar to the conditions of Whitlock and coworkers. 28 Products were purified by column chromatography with hexanes followed by recrystallization from methanol. Colorless flakes are collected at a 24% yield. 1 H NMR (500 MHz, CDCl3): δ 7.54 (d 2H), 7.15 (d 2H), 7.11 (s 2H), 4.06 (t4h), 1.85 (m 4H), 1.53 (m 4H), 1.39 (m 8H), 0.95 (m 6H). 2,6-bis(hexyloxy)naphthalene (1 equiv.) is then stirred at 0 o C to a slurry of iron powder (0.4 equiv.) in carbontetrachloride (ca. 1 ml solvent / g reactant). nce dissolved, bromine (2 equiv.) is added slowly and the reaction is sealed and stirred at 0 o C for 30 minutes before being quenched with a 10% sodium sulfite solution. Products are extracted with methylenechloride and recrystallized from methanol to yield white needles of Np6 at 77% yield. For Np6, 1 H NMR (500 MHz, CDCl 3 ): δ 8.21 (d 2H), 7.32 (d 2H), 4.18 (t 4H), 1.88 (m 4H), 1.57 (m 4H), 1.39 (m 8H), 0.94 (m 6H). 13 C NMR (400 MHz, CDCl 3 ): δ = 14.0, 22.6, 25.6, 29.4, 31.5, 70.3, 109.4, 116.7, 127.2, 129.3, 152.3. MS (EI): found = 484.0608 (M + ), calcd for C 22 H 30 2 2 (M + ) = 484.0612. nature chemistry www.nature.com/naturechemistry 9

supplementary information 10 nature chemistry www.nature.com/naturechemistry

supplementary information 5-bromo-2,6-bis(hexyloxy)-1-naphthaldehyde (Np6A, 7). The title compound was H synthesized from Np6 via the formylation procedure of 6A. Products were purified by silica column chromatography with ethylacetate:hexane (1:30) followed by recrystallization from methanol. Yellow powder is collected from various unwanted products at a yield of only 7%. For Np6A (8), 1 H NMR (500 MHz, CDCl 3 ): 10.89 (s 1H), 9.3 (d 1H), 8.53 (d, 1H), 7.36 (m 2H), 4.22 (t 2H), 4.18 (t 2H), 1.88 (m 4H), 1.54 (m 4H), 1.37 (m 8H), 0.92 (m 6H). 13 C NMR (400 MHz, CDCl 3 ): δ = 14.0, 14.0, 22.5, 22.6, 25.6, 25.7, 29.2, 29.3, 29.4, 31.5, 31.5, 69.7, 70.1, 109.8, 115.4, 116.5, 118.3, 125.7, 127.6, 128.3, 135.6, 152.5, 162.5, 191.9. MS (EI): found = 434.1460 (M + ), calcd for C 23 H 31 3 (M + ) = 434.1456. A portion of Np6 remains in the product of this reaction and was unremoved through several recrystallizations and columns. This can be seen in the following NMR spectra and was accounted for when Np6A and Np6 were mixed to produce orange-emitting crystals. nature chemistry www.nature.com/naturechemistry 11

supplementary information H 12 nature chemistry www.nature.com/naturechemistry

supplementary information Structure Determination Colorless plates of 6 (2) were grown from a methanol solution at 25 o C. A crystal of dimensions 0.40 x 0.36 x 0.06 mm was mounted on a standard uker SMART 1K CCD-based X-ray diffractometer equipped with a LT-2 low temperature device and normal focus Mo-target X-ray tube (λ = 0.71073 A) operated at 2000 W power (50 kv, 40 ma). The X-ray intensities were measured at 108(2) K; the detector was placed at a distance 4.912 cm from the crystal. A total of 4095 frames were collected with a scan width of 0.5 in ω and phi with an exposure time of 20 s/frame. The integration of the data yielded a total of 15030 reflections to a maximum 2θ value of 56.64 of which 2332 were independent and 2189 were greater than 2σ(I). The final cell constants (Supplementary Table 1) were based on the xyz centroids of 5428 reflections above 10σ(I). Analysis of the data showed negligible decay during data collection; the data were processed with SADABS and corrected for absorption. The structure (Supplementary Figure 2) was solved and refined with the uker SHELXTL (version 6.12) software package, using the space group P1bar with Z = 1 for the formula C 18 H 28 2 2. All non-hydrogen atoms were refined anisotropically with the hydrogen atoms placed in idealized positions. The molecule lies on an inversion center in the crystal lattice. Full matrix least-squares refinement based on F 2 converged at R1 = 0.0190 and wr2 = 0.0497 [based on I > 2sigma(I)], R1 = 0.0213 and wr2 = 0.0506 for all data. Colorless blocks 6A (1) were grown by slow evaporation of a methanol solution at 25 o C. A wedge-shaped crystal of dimensions 0.27 x 0.22 x 0.15 mm was cut from a larger mass and mounted on a uker SMART APEX CCD-based X-ray nature chemistry www.nature.com/naturechemistry 13

supplementary information diffractometer equipped with a low temperature device and fine focus Mo-target X-ray tube (λ = 0.71073 A) operated at 1500 W power (50 kv, 30 ma). The X-ray intensities were measured at 85(1) K; the detector was placed at a distance 5.055 cm from the crystal. A total of 4095 frames were collected with a scan width of 0.5 in ω and 0.45 in phi with an exposure time of 15 s/frame. The integration of the data yielded a total of 33365 reflections to a maximum 2θ value of 56.72 of which 4669 were independent and 4444 were greater than 2σ(I). The final cell constants (Supplementary Table 2) were based on the xyz centroids of 9960 reflections above 10σ(I). Analysis of the data showed negligible decay during data collection; the data were processed with SADABS and corrected for absorption. The structure (Supplementary Figure 3) was solved and refined with the uker SHELXTL (version 6.12) software package, using the space group P1bar with Z = 2 for the formula C 19 H 29 3. All non-hydrogen atoms were refined anisotropically with the hydrogen atoms placed in idealized positions. Full matrix leastsquares refinement based on F 2 converged at R1 = 0.0225 and wr2 = 0.0606 [based on I > 2sigma(I)], R1 = 0.0241 and wr2 = 0.0615 for all data. Sheldrick, G.M. SADABS, v. 2007/4. Program for Empirical Absorption Correction of Area Detector Data, University of Gottingen: Gottingen, Germany, 2007. Sheldrick, G.M. SHELXTL, v. 6.12; uker Analytical X-ray, Madison, WI, 2001. Sheldrick, G.M. CELL_NW, Program for Indexing Twins and ther Problem Crystals, University of Gottingen: Gottingen, Germany, 2003. Sheldrick, G.M. TWINABS, v. 1.05. Program for Empirical Absorption Correction of Area Detector Data, University of Gottingen: Gottingen, Germany, 2005. Saint Plus, v. 7.34, uker Analytical X-ray, Madison, WI, 2006. 14 nature chemistry www.nature.com/naturechemistry

supplementary information 6A Supplementary Figure 3. Crystal unit cell of 6A. Supplementary Table 1. Structure data of 6A. Name 6A Formula C 19 H 29 1 3 Space Group P-1 Cell Lengths a 9.5083(8) b 9.6863(8) c 10.9481(9) Cell Angles α 68.5630(10) β 85.8470(10) γ 84.9170(10) Cell Volume 934.004 Z, Z Z: 2 Z : 0 R-Factor (%) 2.25 nature chemistry www.nature.com/naturechemistry 15

supplementary information 6 Supplementary Figure 3. Crystal unit cell of 6 Supplementary Table 2. Structure data of 6. Name 6 Formula C 18 H 28 2 2 Space Group P-1 Cell Lengths a 6.8032(10) b 8.117(3) c 9.659(3) Cell Angles α 108.27(3) β 106.91(3) γ 96.94(2) Cell Volume 471.218 Z, Z Z: 1 Z : 0 R-Factor (%) 1.9 24 Kim, H.-J., Lee, J., Kim, T.-H., Lee, T.S. & Kim, J. Highly Emissive Self-assembled rganic Nanoparticles having Dual Color Capacity for Targeted Immunofluorescence Labeling. Advanced Materials 20, 117-1121, (2008) 25 Wu, C.-W. & Lin H.-Cheu H-Bonded Effects on Novel Supramolecular Dendrimers Containing Electron-Transporting Donor Dendrons and Single/Double H-Bonded Acceptor Emitters. Macromolecules 39, 7985-7997 (2006). 26 Rehahn, M., Schlüter, A.-D. & Feast, W.J. A High-Yield Route to 2,5-di-n-alkyl-1,4- benzenedicarboxylic Acids. Synthesis 5, 386-388, (1988). 27 Gao, P., Feng, X., Yang, X., Enkelmann, V., Baumgarten, M. & Müllen, K. Conjugated Ladder-Type Heteroacenes Bearing Pyrrole Thiophene Ring Unitrs: Facile Synthesis and Characterization. J. rg. Chem. 73, 9207-9213, (2008). 28 Whitlock, B.J., Jarvi, E.T. & Whitlock, H.W. Preparation and Characterization of 1,8,19,26-Tetraoxa[8,8](2,6)naphthalenophane-3,5,21,23-tetrayne and Related Donut- Shaped Cyclophanes. J. rg. Chem. 46, 1832-1835 (1981). 16 nature chemistry www.nature.com/naturechemistry